Pneumologie 2015; 69 - A32
DOI: 10.1055/s-0035-1556624

Constitutive Fgf10 deficiency leads to impaired embryonic lung development

F Yahya 1, 2, 3, CM Chao 1, 2, 3, S Bellusci 1, 2, 3
  • 1Excellence Cluster Cardio-Pulmonary System, Gießen, Germany
  • 2University of Gießen and Marburg Lung Center, Gießen, Germany
  • 3Justus-Liebig-University Gießen, Germany

Objective:

Fgf10 is known to be essential for lung development and regeneration. Our previous data showed that reduced Fgf10 expression leads to delayed embryonic lung development. The aim of this project is to investigate the role of constitutive Fgf10 deficiency in normoxic and hyperoxic condition (BPD mouse model).

Methods:

  • Transgenic mouse line of constitutive Fgf10 deficiency (Fgf10+/-, Fgf10 LacZ/-):
    In WT vs. Fgf10+/- and WT vs. Fgf10 LacZ/- gene expression analyses (whole lung) at E12.5, E18.5 and PN70 were done by using qRT – PCR (real-time PCR).

  • BPD mouse model: WT vs. Fgf10+/- mice were exposed to 85% O2 (hyperoxia) from PN0-PN3. Lungs were harvested at PN3 and gene expression analyses (whole lung) were performed by using real-time PCR. Results were compared to control group under normoxic conditions.

  • Gene expression analyses from 1) and 2) were confirmed on protein level by immunofluorescence (IF) staining (SPC, PECAM, ECAD, KI67).

Results:

  • Fgf10 expression is decreased in Fgf10+/- (by 50%) and Fgf10 LacZ/- (by 80%) mouse lungs.

  • Constitutive Fgf10 deficiency causes significant changes in gene expression at E18.5 (Fgf10+/- and Fgf10 LacZ/- vs. WT): Decreased epithelial marker, increased Tgf-ß signaling and increased of inflammation markers. Under hyperoxic conditions (hyperoxia PN0-PN3) gene expression is significantly increased for collagen markers, cell cycle genes and Tgf-ß signaling in Fgf10+/- vs. WT.

  • In Fgf10+/- mouse lungs at PN3 the IF for Surfactant Protein C (SPC) leads to a considerable decrease of SPC positive cells after hyperoxic injury compared to WT.

An ECAD/KI67 antibody double immunofluorescence staining shows a highly significant increase of proliferating cells (KI67 positive) at PN3 after hyperoxic injury in Fgf10+/- vs. WT, whereby only a quarter of these cells are ECAD positive.

Conclusion:

Constitutive Fgf10 deficiency causes changes in gene expression and on protein level relevant for lung development.

*Presenting author